The objectives of ths proposal are to extend and corroborate and determine the interrelationship of three preliminary observations associated with disease progression and death in patients with solitary, resectable classical osteogenic sarcoma. The three findings are the inability to confer adoptive skin delayed type hypersensitivity reactivity to common microbial antigens with dialysable transfer factor, the appearance of circulating tumor cells immediately before, during or following amputation of the tumor-bearing limb and an elevated tumor alkaline phosphatase level. It is postulated that these factors witness both a deficit in the immune homeostatis reserve of the patient on one hand and a high level of tumor malignancy on the other hand. It is suggested that one or more of these findings will identify post-surgical patients at high risk and who require vigorous adjuvant therapy and another group of low risk patients who may not need any additional adjunctive measures.